10209 has 8 divisors (see below), whose sum is σ = 14112. Its totient is φ = 6560.

The previous prime is 10193. The next prime is 10211. The reversal of 10209 is 90201.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 10209 - 2⁴ = 10193 is a prime.

It is a nialpdrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 10194 and 10203.

It is not an unprimeable number, because it can be changed into a prime (10259) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 82 + ... + 164.

It is an arithmetic number, because the mean of its divisors is an integer number (1764).

2¹⁰²⁰⁹ is an apocalyptic number.

It is an amenable number.

10209 is a deficient number, since it is larger than the sum of its proper divisors (3903).

10209 is an equidigital number, since it uses as much as digits as its factorization.

10209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127.

The product of its (nonzero) digits is 18, while the sum is 12.

The square root of 10209 is about 101.0395961987. The cubic root of 10209 is about 21.6934055153.

It can be divided in two parts, 1020 and 9, that multiplied together give a triangular number (9180 = T₁₃₅).

The spelling of 10209 in words is "ten thousand, two hundred nine".